552093440domain: NAppears in sequences1/6 the number of colorings of a 4 X 4 rhombic- or staggered- hexagonal array with n colors.at n=3A0682451/6 the number of colorings of an n X n rhombic hexagonal array with 6 colors.at n=3A0682731/6 the number of colorings of an n X n staggered hexagonal array with 6 colors.at n=3A068285